Chapter 11: Arenes and Aromaticity
Nucleophilic Substitution of Benzylic Halides
Reaction type: Nucleophilic substitution (S
N
1 or S
N
2)
Summary
Benzylic halides undergo nucleophilic substitution reactions very readily (
review
)
1
o
benzylic halides typically react via an S
N
2 pathway (
review
), and there is no competition from elimination.
2
o
or 3
o
benzylic halides typically react via an S
N
1 pathway (
review
), via the
resonance stabilised carbocation
.
Unlike
allylic systems
, there is no "benzylic rearrangement" since that would result in loss of aromaticity.
Example
:
Related reactions
Nucleophilic substitution of alkyl halides
Nucleophilic substitution of allyl halides
©
Dr. Ian Hunt
, Department of Chemistry